"I'm pretty sure the servant to whom she's referring was the one played by Emma Thompson, not Anthony Hopkins. Like her, Blair has such expressive hands. ..."

Would he stop playing peekaboo with his pre-meal moist towels during airplane interviews? Would he quit scrunching up his face and wiggling his eyebrows at memorial services? Would he replace levity and inanity with gravity?

“In many regards, the Bush I knew did not seem to be built for what lay ahead,’’ wrote Frank Bruni, the Times writer who covered W.’s ascent, in his book “Ambling Into History.” “The Bush I knew was part scamp and part bumbler, a timeless fraternity boy and heedless cutup, a weekday gym rat and weekend napster, an adult with an inner child that often brimmed to the surface or burst through.”

The open-microphone incident at the G-8 lunch in St. Petersburg on Monday illustrated once more that W. never made any effort to adapt. The president has enshrined his immaturity and insularity, turning every environment he inhabits — no matter how decorous or serious — into a comfortable frat house.

No matter what the trappings or the ceremonies require of the leader of the free world, he brings the same DKE bearing and cadences, the same insouciance and smart-alecky attitude, the same simplistic approach — swearing, swaggering, talking to Tony Blair with his mouth full of buttered roll, and giving a startled Angela Merkel an impromptu shoulder rub. He can make even a global summit meeting seem like a kegger.

Catching W. off-guard, the really weird thing is his sense of victimization. He’s strangely resentful about the actual core of his job. Even after the debacles of Iraq and Katrina, he continues to treat the presidency as a colossal interference with his desire to mountain bike and clear brush.

In snippets of overheard conversation, Mr. Bush says he has not bothered to prepare any closing remarks and grouses about having to listen to other world leaders talk too long. What did he think being president was about?

The world may be blowing up, and the president may have a rare opportunity to jaw-jaw about bang-bang with his peers, but that pales in comparison with his burning desire to return to his feather pillow and gym back at the White House.

“Gotta go home,’’ he tells the guy next to him. “Got something to do tonight. Go to the airport, get on the airplane and go home.” A White House spokesman said Mr. Bush had nothing on his schedule after he returned to Washington on Monday about 4 p.m.

When he began meandering about how big Russia was, you expected him to yell, “Yo, Condi!’’ and ask his secretary of state: “Hey, what’s the name of that other big country that has more people than any other country in the world? It begins with a ‘C.’ Dad spent some time there.’’

Perhaps it’s that anti-patrician chip on his shoulder, his rebellion against a family that prized manners and diplomacy above all. But when bored or frustrated, W. reserves the right to be boorish — no matter if the setting is a gilded palace or a Texas gorge.

He treated Tony “As It Were” Blair like the servant in “The Remains of the Day,’’ blowing off his offer to help with the Israel-Lebanon crisis, and changing the subject from substance to fluff at one point, noting about his 60th-birthday Burberry gift: “Thanks for the sweater. Awfully thoughtful of you.’’ Then he razzed the British prime minister, who was hovering and wheedling like an abused wife: “I know you picked it out yourself.”

After doing his best to undermine the U.N. and Kofi Annan, W. talked about the secretary general like a fraternity pledge he wanted to send out for more beer or a keg of Diet Coke: “I felt like telling Kofi to get on the phone with Assad and make something happen.’’

His loosey-goosey confidence that everything could be fixed with a phone call — and not even a phone call made by him, and not even a phone call made to the Iranians, who have more control over Hezbollah — was striking. He seems to have no clue that his own headlong, heedless actions in the Middle East have contributed to the deepening chaos there, and to Iran’s growing influence and America’s diminished leverage.

Mr. Bush may resent the sophistication required of a president. But when the world is going to hell, he should stop chewing and start thinking.

A version of this op-ed appeared in print on July 19, 2006, on page A21 of the New York edition with the headline: Animal House Summit.